#include <stdio.h>

int main()
{
    
    // char a[] = {0x11,0x22,0x33,0x44};
	// char t = a[3];
	// a[3] = a[0];
	// a[0] = t;
	// t = a[1];
    // a[1] = a[2];
    // a[2] = t;
	// int*p = (int*)a;
    // int data = *p;
	// printf("data = %#x\n", data);
 
    // ==========================================
        // char a[] = {0x11,0x22,0x33,0x44};
        // int data;
        // char*p = (char*)&data;
        // *p = a[3];//p[0] = a[3]
        // *(p+1) = a[2];
        // *(p+2) = a[1];
        // *(p+3) = a[0];
        // printf("data = %#x\n", data);
    // ===========================================
    char a[] = {0x11,0xff,0x33,0x44};

    int data = (a[0]&0xff) << 24 | (a[1]&0xff) << 16 | (a[2]&0xff) << 8 | (a[3]&0xff);
    printf("data = %#x\n", data);
}